Mineral - Aurichalcite
Aurichalcite
Chemical Properties
Mineral Class
Carbonates
Toxicity
none
Formula
(Zn,Cu)₅[(OH)₆|(CO₃)₂]
Unit Cell
a=13.82 b=6.42 c=5.29 β=101° Z=2
Physical Properties
Hardness
1 - 2
Streak
blueturquoiseblue white
Density
Heavy (3,5-6)
Cleavage
Perfect after {010} and {100}
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
whitegreenblueturquoiseblue white
Birefringence
0.089
Luster
Silky,
Pearly
Transparency
translucent,
transparent
Pleochroism
X: Farblos
Y: Blau-Grün
Z: Blau-Grün
Geomineralogical Properties
Crystal System
monoclinic
Point Group
monoclinic-prismatic - 2/m
Space Group
P2 1 /m (11)
Habit
tufty, spherical, acicular, prismatic
Formation
In the oxidation zone of supergene copper and zinc deposits
Paragenesis
Twinning
Rarity
Rather rare
Synonyms
Aurichalcite
Composition
Elements
Mass
CO₂
16.22
CuO
19.87
ZnO
54.01
CaO
0.36
H₂O
9.93
Utah (Palache et al. 1952)
Name and first discovery : Named after the ancient Greek word "aurichalcum" for "yellow copper" in reference to its composition.
Chemistry :
Synonyms : Buratite, Messingite, Orichalcite, Rissesite, Auricalcite
Varieties :
Abbreviation : Ach
literature
Palache, C., Berman, H., & Frondel, C. (1952). Dana's system of mineralogy. Geologiska Föreningen i Stockholm Förhandlingar , 74 (2), 218-219.